1.1 This specification covers PTFE-fluorocarbon resin cast film in thicknesses from 0.025 to 0.127 mm (0.001 to 0.005 in.).

1.2 PTFE film and sheet are made by several different processes and the properties of the products reflect both the different starting polymers and the different processes. Properties that are affected include, but are not limited to: tensile strength and elongation at break, porosity, anisotropy, and molecular weight. A related standard is Specifications D 3308. It is important to examine each of the other standards to select the one appropriate for the application.

1.3 The values in SI units are to be regarded as standard. The SI units given in parentheses are for information only.

Note 1—There is no similar or equivalent ISO standard.

1.4. The following precautionary caveat pertains only to the test methods portion, Section 7, of this specification. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.